Colonizing antibiotic resistant bacteria often exists within functionally structured microbial communities, where occurrence is influenced by dependencies essential to stability and function. Considering these interactions could improve understanding of factors influencing diversity of colonizing resistant bacteria within human community settings. Using a framework that considered biotic interactions, we reexamined factors associated with assemblage of colonizing antibiotic resistant Escherichia coli strains in a densely populated urban informal settlement. We identified antibiotic selection, colonization legacy, positive feedbacks and dispersal as key assembly processes. Antibiotics and colonization legacy exerted strain-specific effects while dispersal factors influenced all strains rather uniformly. Specifically, areas frequently exposed to bactericidal antibiotics were dominated by locally established resistant strains, whereas areas frequently exposed to bacteriostatic antibiotics had increased presence of less-established strains. Assemblage configuration was influenced by relative abundance of strains initially present in and around the disturbed areas. Hygiene practices reinforced local strains consistently while weather variables had variable effects: high monthly average minimum temperatures increased abundance of nearly all strains, whereas increases in monthly average maximum temperature, humidity, and rainfall uniformly decreased strain abundance. Overall, we show that survival selection, driven by selective forces, and dispersal selection, shaped by colonization potential, jointly influenced strains recruitment and assembly, suggesting antibiotics and priority effects as factors contributing to resistant E. coli assemblages in this setting. Together these findings underscore need for context-specific antibiotic stewardship and hygiene interventions.
Prosthetic joint infection (PJI) after total shoulder arthroplasty (TSA) is a devastating complication. Cephalosporins are considered the standard of care for antibiotic prophylaxis during TSA procedures; however reported β-lactam allergies may result in the use of less effective alternatives which are associated with higher infection and complication rates. The aim of this study is to evaluate the relationship between reported β-lactam allergies, antibiotic choice, and revision rates in TSA. A retrospective chart review was conducted on all TSA procedures performed at a single institution between January 2015 and January 2025. Information was collected regarding reported allergies to antibiotics including allergy severity and specific reactions. Additionally, all antibiotics administered during the procedures, intraoperative reactions to administered antibiotics, surgical complications, and subsequent revision procedures were collected. Revision procedures were categorized as septic or aseptic based on preoperative diagnosis. Perioperative antibiotics and patient allergies were categorized into penicillins, cephalosporins, clindamycin, vancomycin and other. Data from 4,232 TSAs were collected. 23% of patients had a reported antibiotic allergy and 15% had a β-lactam allergy. Cephalosporins were administered in 94% of all TSAs, but use declined with increasing β-lactam allergy severity, dropping from 90% in mild cases to 44% in severe cases, with corresponding increases in clindamycin and vancomycin use. Higher allergy severity was strongly associated with reduced cephalosporin use and increased alternative antibiotic use (OR = 0.40, p<.001). Notably, cephalosporins were given to patients labeled as having anaphylactic reactions to penicillins or cephalosporins with no adverse events reported. Overall, intraoperative cephalosporin prophylaxis was significantly associated with decreased all-cause revision odds (OR = 0.47, p<.001) and the presence of a β-lactam allergy was associated with increased likelihood requiring a revision procedure for a presumed septic etiology. The severity of reported β-lactam allergies strongly influences perioperative antibiotic selection despite evidence that most reported allergies are unreliable, unnecessarily increasing patient risk for PJI. Lack of cephalosporin prophylaxis was associated with increased revision rates, underscoring the clinical and economic value of appropriate antibiotic use. Given the high prevalence of mislabeled β-lactam allergies, established delabeling strategies using allergy testing or test-dosing in the operating room may offer a safe and effective means to increase first-line antibiotic use and improve stewardship. Level III, Retrospective Cohort Comparison, Prognosis Study.
Breath analysis offers a promising, non-invasive approach for early disease detection in livestock, particularly for bovine respiratory disease (BRD). However, the widespread use of antibiotics in veterinary practice raises concerns about their potential to confound breath-based diagnostics. In this study, we analysed breath samples from 65 calves to evaluate the diagnostic performance of volatile organic compounds (VOCs) as biomarkers of BRD. We identified several candidate ions, including formaldehyde and acetone/propanal, that showed significant elevation at the onset of disease and a modest detection capability (AUC = 0.53-0.77). However, the strongest discrimination between diseased and controls occurred after antibiotic administration, suggesting a confounding pharmacological influence. To isolate this effect, a secondary trial was conducted in which healthy calves were treated with oxytetracycline dihydrate (Alamycin® LA 300). This revealed rapid and transient changes in the breath volatilome, with significant increases in dimethyl sulphide and (C₅H₁₀O)H+ within 1 hour, and other VOCs, including formaldehyde and acetone/propanal within 24 hours of treatment. These findings demonstrate that antibiotics can substantially alter breath VOC profiles, potentially mimicking or masking disease signals. We conclude that breath-based diagnosis of BRD holds promise but must account for treatment history to avoid misclassification. Moreover, the reproducible and time-resolved nature of the VOC response suggests that breath analysis could also be developed as a tool for monitoring antimicrobial exposure and optimising therapeutic dosing in livestock.
Natural products remain a major source of antibiotics, but discovery efforts have traditionally treated biosynthetic gene clusters as sources of individual bioactive molecules1-5. Increasing evidence has suggested that microorganisms can instead encode coordinated multi-metabolite systems, yet the genetic architectures and biological logic of such systems remain poorly understood6-12. Here we show that Streptomyces spp. encode a highly conserved biosynthetic megacluster that produces four structurally distinct natural product families-stravidins, acidomycin, dapamycins, and 2-methyl-7-keto-8-aminopelargonic acid (α-Me-KAPA)-alongside the biotin-binding protein streptavidin. These components converge on bacterial biotin metabolism through complementary mechanisms, including enzyme inhibition, prodrug activation, cofactor mimicry and biotin sequestration. The encoded metabolites are co-produced and act synergistically across Gram-negative and mycobacterial species, with stravidin S2 and α-Me-KAPA showing enhanced efficacy in combination in a mouse model of multidrug-resistant Escherichia coli infection. This megacluster reveals a genetically encoded chemical arsenal that functions as a naturally evolved combination therapy against a conserved metabolic pathway. More broadly, our findings suggest that higher-order biosynthetic architectures may represent an overlooked reservoir of antibiotic mechanisms and support a shift from discovering isolated natural products to reconstructing native synergistic systems.
Antibiotics and antibiotic resistance genes (ARGs) in coastal urban waters pose increasing environmental and public health risks due to their persistence and their role in accelerating antimicrobial resistance (AMR), yet their dynamics remain difficult to predict under data-scarce conditions. This study developed an integrated multi-model framework that combines a process-based hydrological model, a modified LOADEST model, multiple machine learning approaches, and Shapley additive explanations (SHAP) for interpretability to predict antibiotics and AMR indicators (mainly ARGs) in three coastal zones of Singapore. Using readily available hydrometeorological datasets and limited routine water quality variables, the framework achieved robust performance, with the Long Short-Term Memory (LSTM) model performing best among the machine learning models. The LSTM-based integrated framework showed good predictive performance for low-censored antibiotics, as exemplified by clarithromycin (CLAR; NSE = 0.62 ± 0.13), and most AMR indicators across the three coastal zones (average NSE = 0.67 ± 0.10), whereas predictive performance decreased for highly censored antibiotics due to the limited information available for learning temporal variability. SHAP feature analysis showed that routine water quality variables and flow dominated model predictions, while meteorological factors were less influential, and SHAP temporal patterns further indicated that antibiotic responses to environmental drivers occurred on timescales comparable to catchment-to-coastal hydrological transport times, whereas ARGs consistently exhibited longer lagged responses across all regions. Incorporating predicted CLAR as an input feature in the macrolide-associated ARG model identified a positive association between CLAR and ARG only in the region with relatively high CLAR concentrations, and SHAP-derived interaction strengths showed that CLAR interacted most strongly with routine water quality variables, followed by hydrological factors, with weak interactions observed for meteorological variables. Overall, the proposed framework provides a practical and transferable hybrid modelling approach for predicting antibiotic and ARG dynamics in data-limited coastal environments.
Acute otitis media is among the most common childhood infections and a major source of antibiotic use. Evidence from randomized trials shows that around 80% of cases resolve spontaneously, with antibiotics offering only modest symptomatic benefit and causing frequent adverse effects. Watchful waiting-with accurate diagnosis, effective analgesia, and clear safety-netting-achieves equivalent outcomes to immediate treatment in most children. Antibiotics remain essential for infants aged under 6 months, bilateral or suppurative disease, and high-risk groups. Aligning practice with evidence supports safer, more rational care and helps mitigate antimicrobial resistance.
The use of antibiotics to promote growth and prevent disease in livestock and poultry animals has raised concerns about antimicrobial resistance and its consequences for public health. Increasing pressure on the livestock and poultry industries demands improved productivity, reduced economic losses, and the assurance of food safety for human consumption. Plant bioactive compounds (PBCs) have emerged as safe and sustainable alternatives to antibiotics that promote the growth, support animal health and improve productivity without compromising food safety. PBCs represent a diverse group of secondary metabolites-including phenolics, terpenoids, polysaccharides, and organosulfur compounds-that exhibit a wide range of biological activities relevant to livestock and poultry nutrition and health. Recent studies have shown that supplementing animals with PBCs as feed additives, either as crude extracts or individual compounds, improves growth performance, nutrient utilization, and modulates gut microbiota, while also exerting antioxidant, anti-inflammatory, antimicrobial, and immunoregulatory effects, thereby enhancing overall resilience of animals. The multifunctional properties of PBCs, and the reduced risk of resistance development position them as promising candidates for next-generation feed additives for livestock and poultry production. However, challenges remain regarding optimal concentration, variability in bioavailability, stability during feed processing, and the standardization of active components. Here, we discuss the major PBCs and their potential as functional feed additives to improve livestock and poultry production. We further highlight research gaps and outline future prospects required to advance their adoption in sustainable animal production.
The diagnosis of acute community-acquired bacterial urinary tract infections (UTIs) in adult men presently recognizes four key clinical entities: cystitis, prostatitis, pyelonephritis, and epididymo-orchitis, each with distinct diagnostic criteria. Bacteriuria of clinically undetermined significance, defined as documented bacteriuria with non-specific systemic symptoms (e.g., confusion, functional decline, or isolated fever) but no localized UTI signs, is common in elderly patients and requires evaluation with sepsis risk scores so as to avoid unnecessary antibiotics. Urinary colonization, frequent in older men, does not warrant treatment unless prior to urological procedures. Cystitis is diagnosed by local symptoms (dysuria, urgency, suprapubic pain), absence of fever, and positive urine culture, ruling out prostatitis or pyelonephritis. Acute prostatitis is identified by cystitis symptoms plus fever or sepsis, with imaging reserved for complications. Acute pyelonephritis is diagnosed by fever or sepsis, flank pain (spontaneous or on percussion), and positive urine culture; cystitis symptoms may be absent. Urine culture (thresholds: ≥103 CFU/mL for bacteriuria, leukocyturia >30 × 103/mL) remains the gold standard, while urine dipstick testing is not recommended due to low predictive value. Routine blood tests (inflammatory markers, PSA, or blood cultures) are unnecessary in outpatient management, even for febrile UTIs, unless acute kidney injury or complications are suspected. Pyelonephritis requires imaging (urgent in cases of sepsis or obstruction) to assess for uropathy, and epididymo-orchitis mandates STI screening.
Under low concentrations of antibiotics causing DNA damage, Escherichia coli bacteria can trigger stochastically a stress response known as the SOS response. While the expression of this stress response can make individual cells transiently able to overcome antibiotic treatment, it can also delay cell division, thus impacting the whole population's ability to grow and survive. In order to study the trade-offs that emerge from this phenomenon, we propose a bi-type age-structured population model that captures the phenotypic plasticity observed in the stress response. Individuals can belong to two types: either a fast-dividing but prone to death "vulnerable" type, or a slow-dividing but "tolerant" type. We study the survival probability of the population issued from a single cell as well as the population growth rate in constant and periodic environments. We show that the sensitivity of these two different notions of fitness with respect to the parameters describing the phenotypic plasticity differs between the stochastic approach (survival probability) and the deterministic approach (population growth rate). Moreover, under a more realistic configuration of periodic stress, our results indicate that maximal population growth can only be achieved through fine-tuning simultaneously both the induction of the stress response and the repair efficiency of the damage caused by the antibiotic.
This study aimed to explore the culturable bacterial community in healthy volunteers, with a focus on the staphylococcal population. First, 120 bacterial isolates were collected from conjunctival swabs of 49 healthy volunteers (aged 18 to 77 years). Isolates were characterized by phenotypic analyses, and 68 of them were confirmed as staphylococci by MALDI-TOF/MS and a multiplex PCR assay. The Staphylococcus strains (n = 68) were tested for resistance to the most relevant clinical antibiotics. Clonal relationships among isolates were evaluated by pulsed-field gel electrophoresis (PFGE), and the presence of mecA and mecC, as well as pvl genes, was investigated. Staphylococcus aureus (74%) was the major identified species, followed by Staphylococcus epidermidis (19%) and Staphylococcus xylosus (7%). A high incidence of resistance was detected against gentamicin (64%), erythromycin (62%), and penicillin (51%). Moreover, 33 isolates (48%) exhibited multidrug-resistant phenotypes, and the two S. epidermidis strains harbouring the mec genes exhibited the highest resistance. A marked heterogeneity among isolates, mostly for S. aureus and S. epidermidis, was revealed, clustering them into 20 and 4 genotypes, respectively. The prevalence of the same clones, isolated from different volunteers, across the three species, and the different phenotypic resistance patterns within the same PFGE type, was observed. These findings corroborate that staphylococci constitute a significant component of the ocular microbiota in healthy individuals; however, their exhibited antimicrobial resistance profiles are of concern.
Neutropenia is an adverse event of systemic chemotherapy with various complications that impact patient management, quality of life, and could be fatal. The study was conducted to evaluate chemotherapy-induced-neutropenia in a Palestinian cohort of patients with solid malignancies. This paper examines patient characteristics, risk factors for neutropenia severity and management patterns. The study included a total of 171 adult patients diagnosed with solid malignancies, and were on their first chemotherapy regiments with no history of neutropenia. Data was collected retrospectively from patients' electronic medical records. Only patients who developed neutropenia during treatment were included in this study, and were classified into three groups of severity based on the absolute neutrophil count. Colon cancer and lung cancer were the most reported. Epirubicin, paclitaxel, cyclophosphamide, and doxorubicin were significantly associated with neutropenia severity, in addition to the number of chemotherapy cycles, stage at diagnosis and certain comorbidities. 32.5% of patients reported substance use which was also significantly associated with severity. The majority of patients received primary GCSF prophylaxis. 69% of patients presented with febrile neutropenia. Hospitalization, antibiotics, antipyretics, and GCSF were utilized for management in most patients. Neutropenia severity was associated with the chemotherapy agents used, while the type of solid malignancy was not. Substance use represented a high burden among our cohort, and its association with severity could be further studied. Primary GCSF prophylaxis is critical with patients not receiving it developing profound neutropenia (absolute neutrophil count < 0.1 x 109) at higher rates.
Severe mpox in people living with HIV remains poorly characterised in African settings experiencing Clade 1b transmission. We characterised the clinical, virological, microbiological, and immunopathological features of critical illness during the 2025 mpox outbreak in Uganda. We conducted a prospective cohort study of 155 consecutively hospitalised adults with mpox in Uganda between 3 March and 10 April 2025 and performed a nested analysis of critically ill participants. Critically ill participants with sequencing-confirmed Clade Ib infection underwent compartment-specific MPXV PCR testing, lesion bacterial culture and antimicrobial susceptibility testing, HIV viral load assessment, and routine haematological and biochemical investigations. Ten of 155 participants (6.5%) developed critical illness, including four deaths, four severe non-ICU cases, and two ICU admissions. All were people living with HIV. MPXV DNA was consistently detected in skin, genital, and oral/saliva specimens, with substantially lower detection in plasma. Purulent lesion cultures were positive in 9/9 participants and yielded Gram-negative bacilli, Staphylococcus aureus, coagulase-negative staphylococci, and Enterococcus species, demonstrating resistance to multiple commonly used antibiotics. Critically ill participants exhibited anaemia, neutrophilia, relative lymphopenia, hypoalbuminaemia, hyperbilirubinaemia, and elevated C-reactive protein. Most survivors cleared MPXV DNA during follow-up, whereas persistent plasma and anal MPXV DNA detection was observed in one participant who subsequently died. Critical Clade 1b mpox in adults with HIV was characterised by high mucocutaneous viral burden, frequent bacterial superinfection with antimicrobial resistance, and marked systemic inflammatory abnormalities. These findings support integrated management strategies incorporating mucocutaneous diagnostics, antimicrobial stewardship, inflammatory monitoring, and optimisation of HIV care.
Algal-derived extracellular organic matter (EOM) is an important photosensitizer to trigger antibiotics photodegradation in sunlit waters. However, ubiquitous metal ions may substantially alter this process, and the underlying mechanisms remain insufficiently understood. In this study, we systematically investigated the effects of representative metal ions (Fe3+, Cu2+, Cr3+, Zn2+, Mn2+) on the EOM-sensitized photodegradation of sulfamethoxazole (SMX). All tested metal ions inhibited SMX photodegradation to different extents, following the order: Fe3+ ≈ Cu2+ > Cr3+ > Zn2+ ≈ Mn2+. The inhibition strength was strongly correlated with the conditional stability constants (log KSC) of metal-EOM complexes, indicating that metal-EOM complexation dominantely governs the suppression of EOM photosensitization. Fluorescence excitation-emission matrix analysis and triplet-state probe experiments showed that metal binding markedly reduced the formation of excited triplet-state EOM (3EOM*), the key reactive oxygen species (ROS) responsible for SMX transformation. Electron spin resonance analysis further revealed that the production of secondary ROS derived from 3EOM* was also suppressed after complexation. To gain molecular-level insight, representative EOM model compounds were examined using time-dependent density functional theory. The calculations showed that complexation induced ligand-to-metal charge transfer (LMCT) excitation pathways, which provided a plausible electronic mechanism for the competitive dissipation of excitation energy and the observed suppression of triplet-state formation. These findings identify that metal-EOM complexation as an important yet previously underappreciated factor controlling antibiotic photodegradation in aquatic waters, and highlight its relevance for improving predictions of contaminant persistence under environmentally realistic conditions.
Salmonellosis is a major zoonotic disease of poultry that causes substantial economic losses and poses a significant public health risk. Given the growing concern of antimicrobial resistance, this study evaluated the efficacy of lytic bacteriophages against Salmonella enterica serovar Typhimurium in Cobb broiler chicks following in ovo and oral administration. Bacteriophages isolated and maintained in the Department of Veterinary Microbiology, DUVASU, Mathura, were characterized by transmission electron microscopy, demonstrated a broad host range against multiple Salmonella serovars, and showed no lytic activity against non-target bacterial species. The in vivo efficacy of the phages was assessed in 60 broiler chicks allocated to six groups (n=10): oral administration at multiplicity of infection (MOI) 1 and MOI 2, in ovo administration at MOI 1 and MOI 2, challenged control, and unchallenged control. Phage treatment significantly reduced fecal shedding of S. Typhimurium compared with the challenged control group throughout the experimental period. Oral administration at MOI 1 resulted in the greatest reduction in bacterial shedding, while in ovo administration at MOI 2 provided sustained suppression of bacterial colonization. Cecal bacterial counts were significantly lower in all phage-treated groups, with the most pronounced reductions observed at MOI 1. Histopathological examination further demonstrated reduced intestinal lesions and tissue damage in phage-treated birds compared with challenged controls. These findings demonstrate that lytic bacteriophages effectively reduce intestinal colonization and fecal shedding of S. Typhimurium in broiler chickens and highlight their potential as a promising alternative to antibiotics for the control of poultry salmonellosis.
Bronchiectasis is a chronic respiratory disease characterised by irreversible bronchial dilatation, persistent airway inflammation and recurrent infections. Symptoms, particularly cough, sputum production and dyspnoea, are the most immediate and patient-relevant expression of the disease, linking clinical presentation, airway biology and outcomes. While asthma and COPD management algorithms already integrate symptom burden into therapeutic decision-making, bronchiectasis care has historically relied on exacerbation history to guide preventive interventions. Over the past decade, an expanding body of evidence has demonstrated that daily symptoms mirror current infection and inflammation, profoundly impact quality of life, and predict future exacerbations. Comparative analyses across chronic lung diseases further highlight the central role of symptom monitoring in defining disease activity and risk. The updated European Respiratory Society guidelines translate this evidence into clinical practice, marking a paradigm shift from an exacerbation-driven to a symptom-centred and treatable-traits model. This review synthesises clinical, biological and therapeutic insights linking symptoms to bronchiectasis pathophysiology, disease activity and treatment response. We discuss how airway clearance, mucoactive therapy, antibiotics, pulmonary rehabilitation and targeted anti-inflammatory strategies, including dipeptidyl peptidase-1 inhibition, can address specific symptom profiles. We also mention the role of comorbidities and psychosocial management, establishing symptoms as the cornerstone of a holistic, multidimensional care approach. Recognising symptoms as both biomarkers of activity and therapeutic targets represents a major step toward precision medicine in bronchiectasis, aligning clinical management with patient experience and the biological drivers of disease.
Damaged skin barriers create a vulnerable interface for pathogen colonization, and subsequent pathogen invasion significantly delays tissue repair. Hydrogel dressings have been widely applied in clinical wound management as an effective treatment modality. However, prolonged reliance on antibiotics can induce allergic reactions and exacerbate the risk of drug resistance. Therefore, the development of natural hydrogel dressings that are biocompatible, mechanically robust, and antibiotic-free remains a critical technological challenge. In this study, OHA/PVA/HCMC@NaHCO3 composite hydrogels were prepared using oxidized hyaluronic acid (OHA), hydrazine-containing carboxymethylcellulose (HCMC), polyvinyl alcohol (PVA), and sodium bicarbonate (NaHCO3) as the primary components. The high aldehyde content of OHA chemically crosslinked with hydrazine-containing HCMC formed acylhydrazine bonds, while physical crosslinking with PVA and NaHCO3 formed hydrogen bonds. The incorporation of PVA enhanced the mechanical strength of the hydrogel without compromising its high liquid absorption capacity. NaHCO3 imparts notable antibacterial and antioxidant properties to the composite hydrogel. These effects act synergistically with HA, promoting wound healing while preserving HA's intrinsic skin repair functionality. It exhibited potent antibacterial activity against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. In vitro analyses confirmed good biocompatibility and the ability to promote fibroblast proliferation and migration. In a rat full-thickness skin wound model, the OHA/PVA/HCMC@NaHCO3 hydrogel significantly accelerated wound closure, promoted epidermal regeneration, reduced inflammation, and enhanced collagen deposition and tissue remodeling. The drug-free, readily prepared OHA/PVA/HCMC@NaHCO3 composite hydrogels demonstrate promising potential for clinical application in the treatment of infected wounds.
Antibiotics and mycotoxins are both substances derived from microorganisms and occasionally share similar chemical properties. Test procedures used for residual antibiotic analysis might potentially be applied to mycotoxin analysis. This study validated a method for analyzing patulin in apple juice by adapting the analytical method for the antibiotic oxytetracycline. Method validation was performed by recovery tests at 0.05 ppm to evaluate the trueness, repeatability (RSDr), and within-laboratory reproducibility (RSDwr).The validation results for clarified apple juice and cloudy apple juice exhibited sufficient recovery (91% and 86%) and precision (RSDr≦4% and RSDwr≦4%).The interfering peaks were not observed in the chromatograms of blank extracts, indicating sufficient selectivity. The limit of detection was less than 0.01 ppm in both apple juices. This method can help inspect residual patulin in apple juices.
Amphiphilic aminoglycosides offer a promising approach to combat antibiotic resistant Gram-negative bacteria. Here, a series of neamine-based amphiphiles bearing alkyl chains of varying lengths (C4-C16) was synthesized via a concise route through selective modification at the 6'-amino position of neamine. Antibacterial evaluation revealed a chain length-dependent activity, with the C14- and C15-alkyl neamine amphiphiles exhibiting the most potent antibacterial activity against ESKAPE pathogens. The C15 derivative displayed superior activity compared to neamine and synergized with multiple clinical antibiotics against P. aeruginosa. Mechanistic studies indicated that this synergy results from enhanced outer membrane permeability, and cytotoxicity assays confirmed low toxicity at therapeutically relevant concentrations.
Pharmacists, while central to medication safety, face underestimated risks due to their daily exposure to toxic and explosive substances. In compounding pharmacies, handling carcinogenic, mutagenic, and reprotoxic (CMR) substances such as chemotherapy drugs, anesthetic gases, antibiotics, and hormones poses significant health hazards. These substances can cause environmental and secondary contamination through fine powder dispersion or volatile vapors, leading to indirect exposure even with standard protective gear. Explosive and fire risks also abound, especially with volatile solvents like ethanol, acetone, and ethyl ether. These substances are flammable and require careful storage and handling. Accidental chemical reactions, such as the mixing of acids and bases or contact between unstable compounds like picric acid and friction, can result in toxic gas release or explosions. To mitigate these dangers, pharmacies must implement strict preventive measures. This includes the use of fume hoods, appropriate personal protective equipment (PPE), and standardized protocols for hazardous drug preparation. Flammable substances must be stored in ventilated, ATEX-compliant cabinets, and chemicals clearly labeled with updated safety data sheets (SDS). Safe waste management and continuous staff training are also essential. Current challenges, such as drug shortages, force pharmacies to work with unfamiliar raw materials, increasing the risk of accidents. A notable example is potassium clavulanate, a fine powder prone to dust explosions if not carefully managed. Ultimately, ensuring pharmacist safety requires a culture of vigilance, continuous education, and adherence to safety protocols to manage both toxicological and explosive risks effectively.
Acinetobacter baumannii is a multidrug-resistant pathogen known for its robust biofilm formation, leading to persistent infections and treatment failure. Traditional antibiotics often struggle to penetrate these biofilms. Cinnamaldehyde, a plant-derived antimicrobial compound, holds potential as an antibiofilm agent. This study investigates its effects on biofilm formation, EPS production, cell surface properties, oxidative stress response, and gene expression in A. baumannii. This study evaluated the antibiofilm activity of cinnamaldehyde using A. baumannii. Biofilm formation was quantified via crystal violet assay, while structural alterations were visualised using light microscopy, SEM, and CLSM. EPS production and cell surface hydrophobicity were evaluated using phenol-sulfuric acid and MATH assays. Catalase activity was assessed through H₂O₂ sensitivity, and qRT-PCR analysed gene expression. Cytotoxicity was evaluated using the MTT assay on mouse fibroblast cells. Cinnamaldehyde significantly inhibited biofilm formation, with 86.67% reduction at 0.007% (v/v), without affecting planktonic growth. Microscopy revealed disrupted biofilm architecture and reduced microcolony formation. SEM showed reduced EPS and altered cell morphology. EPS quantification confirmed a 33.06% reduction. Cell surface hydrophobicity decreased from 86.76% to 21.93%, impairing bacterial adhesion. H₂O₂ sensitivity increased, indicating reduced catalase activity. Gene expression analysis showed downregulation of bfmR, ompA, csuA/B, and katE. Cinnamaldehyde showed minimal cytotoxicity in mouse fibroblast cells. Cinnamaldehyde effectively inhibits A. baumannii biofilms through structural disruption, EPS reduction, altered surface hydrophobicity, oxidative stress sensitization, and gene suppression. Its non-toxic nature and broad mechanisms highlight its potential as a plant-based antibiofilm agent for controlling resistant infections.